Hydraulic log-barking machine



' March 5, 1946. BUKQWSKY 2,395,845

AULIC LOG-B ARKING MACHINE INVENTOR March 5, 194 H. E. BUKOWSKY HYDRAULIC LOG-BARKING MACHINE.

Filed Jan. 4, 1943 3 Sheets-Sheet 2 v INVENTOR HARRY E. BUKOWSKY ATTORNEYS March 5, 1946. H. E. BUKOWSKY 9 HYDRAULIC LOG-BARKING MACHINE Filed Jan. 4, 1943 3 Sheets-Sheet 5 I I I w "w'" H W H 4 V INVENTOR HARRY E. BUKOWSKY ATJURNtYS Patented Mar. 5, 1946 4 2,395,845 HYDRAULIC LOG-BARKING MACHINE Harry E. Bukowsky, Port signor to Crown Zeller Francisco, Qaliih, a corporation of Nevada Application January 4, 1943, Serial No. 471,260

' 9 Claims.

This application is a continuation in part of my pending application, Serial No. 380,332, filed under date of February 24, 1941, and entitled Hydraulic log-barking machine, now U. 8. Letters Patent No. 2,328,545, dated September 7,1943; and

this present invention similarly relates to hydraulic debarking means adapted for use with logs of various diameters, and also with logs-of varying diameters.

In the log-barking machine of my previous application I provide a circular saw located adjacent the debarking nozzle and so arranged as to cut a kerf in the bark slightly ahead of the point of impact of the debarking jet with the log in order to facilitate the removal of th bark by the jet. I have found, however, that with such wood as hemlock, and many other woods commonly used in the paper industry, it is possibl to do the debarking with the hydraulic jet alone, provided sufiicient force and speed of the jet as discharged from the hydraulic nozzle are maintained and provided location of the point of impact of the jet with respect to the discharging tip of the nozzle remains more or less constant. When such conditions prevail'I have found that, with most varieties of wood, the debarking of the log can be done so rapidly by hydraulic means alone that only a few seconds are required forcompletely debarking a log of say twenty feet in length. When the debarking takes place so rapidly the saw, described in my previous application, cannot be used at all, since the saw cannot cut a kerf through the bark as rapidly as the Jet from the nozzle will perform the debarking operation. With special logs, for example with large logs of Douglas fir, where the bark has a thickness of many'inches, the debarking is not done so rapidly and then the use of the saw in combination-with the nozzle is desirable. The present invention, however, is concerned specifically with the debarking of logs from which the'bark can be quickly and easily removed by the use of the. hydraulic nozzle alone, provided proper conditions are maintained, as above indicated.

One of the objects of this invention is to provide a hydraulic log-barking machine in which the debarking nozzle will always be properly positioned regardless of the size or regardless of anyvariations in the size of the log.

Another object of the invention is to provide such a machine in which the distance from the discharging tip of the nozzle to the point of impact of the jet with the log will be fairly constant regardless of the size of the log or the contour of the 102. I

An additional object is to provide a support for bach OFFICE Townsend, Wash, as-

Corporation, San

the nozzle so arranged that the nozzle jet will always strike the log at the most emcient angle with respect to the log surface for the debarking.

One of the main objections to debarking devices in which the debarking of the log is done by mechanical means, such as the knife barkersmore commonly employed for this purpose, is that a considerable waste occurs due to unavoidable and inadvertent chipping off of wood just below the bark. Since the best part of the wood for many purposes is located next to the bark it is most desirable that, in the debarking operation, only the bark should be removedand none of the wood. under the bark. Even when the debarkingis done hydraulically, care must be taken .not to remove the wood below the bark layer. The force is so great which is now employed with debarking nozzles that it is possible to cut into the wood below th bark with the jet-and, in fact, .even to cut clear through'the 10g withsuch a jet from a hydraulic nozzle. Consequently, even with hydraulic debarking, it is necessary to exercise proper care to avoid waste of material. This may be done by controlling the speed at which the-debarking is done, so that there ,will be proper Speed in moving the debarking nozzle and log with respect to each other to allow the jet to remove the bark and still not permit the jet to cut into the surface of the wood below the bark.

A still further'object of this invention accordingly is to provide a hydraulic log-barking machine in which not only will the jet always be directed at the proper angle against the log, but in which also the speed at which the debarking is done may also be easily adjusted and controlled so that the' debarking will take place in the most efllcient manner and with the least waste of I material.

These and other objects I have been able to obtain by pivotally mounting a. debarking noz-,

' pivoted at a predetermined point in fixed relation to the log axis; and by otherwise arranging thenozzle and associated elements in my machine as hereinafter briefiy described with reference to the accompanying drawings.

In the drawings:

Fig.1 is a fragmentary side elevationof my. log-barking machine;

Fig. 2 is a fragmentary top plan view of the same;

Fig. 3 is a fragmentary, and more or less .diagrammatic, cross section takenon the line 3-3 of Fig. 1 drawn to a larger scale and also illustrating in broken line the position of the nozzle with a log of smaller diameter;

Fig. 4 is a fragmentary section taken on line 4-4 of Fig. 1 with the nozzle and nozzle shoe omitted and showing the pivotal connection for the nozzle;

Fig. 5 is a section through the nozzle taken on line 5-5 of Fig. 3f

Fig. 6 is a view in isometric perspective of the nozzle shoe, showing the same entirely removed from the nozzle;

Fig. 7 is a diagrammatic figure indicating the location and direction of the nozzle jet in the debarking of logs of different diameters; and

Fig. 8 is a diagrammatic representation of the debarking of a crooked log in my machine.

The log 19 (Fig. 1), during the debarking operation, is supported at the forward end of the machine by'a suitable spur center carried on a spindle H which in turn is mounted in suitable thrust and radial load ball bearings. At the opposite end of the spindle I I two sprocket wheels l2 and I3 are rigidly attached. The outer sprocket I3 is adapted to be connected to a suitable driving means (not shown) by which rotation is imparted to the spindle II and thereby to the log l9. It is assumed that such driving means will be provided with proper controls so that the speed of rotation imparted-to spindle and 10g may be controlled as desired by the operator.

The log in is supported 'at the rear end on a spur attached to a spindle l4 which in turn is mounted in a slidable support l5, adjustable longitudinally in any suitable manner to provide for logs of different lengths. Such log-supporting means is described in my application, Ser. No.

380,332,.previously referred to. The spindles H and I4 are in axial alinement and the log, when and a reversely curved portion 21 at one end 7 which terminates in a nozzle tip 23 so formed as to direct a flat jet .of water against the log surface in order to produce a bark-peeling action. The other end of the main section 26 is secured to a pipe joint 29 (Fig. 4) which in turn is joined by a swivel connection 30 to a supply pipe 3| attached to the carriage it. The pipe joint 29 is rotatably supported in brackets 32 depending-from the carriage l8, and the mounting of the nozzle is arranged so as to permit the discharging end or tip of the nozzle to swing up or down in a vertical arc.

placed in the machine is assumed to be positioned,

regardless of its size or of any variations in its contour, with its rotational axis also in alinement with the axes of the spindles II and I4. Means for lifting the log into this position is not shown, but various means may be employed, for example, the positioning means described in my ,copending application, Ser. No. 416,481, filed unjfder date of October 25, 1941, and entitled ,Load

positioning means," now U. S. Letters Patent No.

2,352,895, issued July 4, 1944.

The machine includes a rigid top frame l6 supported at each end on a pair of uprights or columns I l. A carriage I8 is slidably mounted on the top frame 16 (as shown more clearly in Fig. 3).

The carriage I8 is connected to the ends of a sprocket chain l9 which passes over a sprocket wheel 20 at the front end of the top frame It. The sprocket wheel 29 is connected by suitable gearing to a shaft 2|, which in turn is connected with the spindle ll through the intermediary of sprocket wheels 22 and I2 and the connecting sprocket chain 23, so that rotation of the spindle H counter-clockwise, as viewed from the front end, will cause the carriage M8 to move towards the forward end of the machine at a predetermined rate of speed with respect to the rotational speed of the spindle H and log 19. .A magnetic clutch, indicated at 24 in' Fig. 2, is preferably interposed in this'carriage-moving mechanism so A shoe 33, attached to the main nozzle section 26, is adapted to ride on the outer: surface of the log during the debarking operation, and thus, when the nozzle is lowered into debarking position, the shoe keeps the nozzle tip 28 from actual contact with the log but enables the tip to ride very close to the log surface. While the shoe 33 may be made in any number of different shapes I have found it very satisfactory to have the shoe in the form of an inverted U or channel shape (as shown in Figs. 5 and 6) which enables the shoe also to serve as a shield confining the small splinters, into which the bark is broken by the force of the jet from the nozzle, within fairly narrow limits and thus aid in disposing of the same. A shield 41 (Fig. 3) at the end of the shoe aids further in confining and directing the bark splinters.

When the shoe is in this form the bottom edges 34' of the sides 34 provide the bearing surfaces or runners which ride on the outer surface of the bark as the log rotates and the carriage 18 moves towards the front of the machine. The shoe 33 may be attached to the nozzl in any desired manner and may be either rigidly or flexibly connected. In the machine illustrated in the drawings I have preferred to attach the shoe to the nozzle by means of bolts 42 extending through flanges at the top of the shoe and through fins 42 (Fig. 5) on the outside of the nozzle, and to interpose cushioning elements 43 of resilient material in order to absorb some of the vibration of the shoe which is caused in passing rapidly over the surface of a rough log.

The positioning of the debarking nozzle up or down with respect to the supporting carriage I8 is preferably done through the medium of a compressed air cylinder 35 (Fig. 3) mounted on the carriage 18. A suitable control valve element (not shown) is provided through which the cylinder 35 is connected to a source of compressed air through the ports 35'. A lever arm 36, ri idly connected to the pivotally-mounted nozzle, is connected at its upper end to a pair of links 31 which in turn are connected to the guide block 39 on the end of the piston rod 38 of the air cylinder 35. The guide block 39 of the pistonviewed in Fig. 3), while air is allowed to be exhausted through the right hand port 35, the piston rod 38 will be moved to the right and this aseaens will cause the nozzle assembly to be swung u wardly out of debarking position. To .prevent the nozzle from striking against the carriage or frame When the nozzle is swung upwardly quickly I provide a nozzle bumper 4| on the carriage.

When the log is in place in the machine and ready for debarking and the carriage is positioned at the rear end of the log, the nozzle is lowered until the shoerests on the outersurface of the log. This lowering of the nozzle is accomplished by allowing air to enter the port 35' at the right hand end of cylinder 35 (Fig. 3) and be exhausted from the left hand port 35. The weight of the nozzle and shoe will keep the shoe in contact with the log surface and thus the nozzle tip will be held at the proper location with respect to the log. Should the surface of the log be very irregular, the air cylinder 35 will Dermit sufficient play in the up and down movement of the nozzle and shoe to enable them to follow the contour of the log, and at the same time the air cylinder and piston provide a desirable cushioning means preventing excessive bouncing of the shoe and nozzle when the log is being rotated rapidly and its surface is very irregular and also holds the nozzle against any kick back.

When the debarking is to be done entirely by the jet of water from a hydraulic nozzle in a debarking machine, I have found that the angle at which the jet is directed against the bark is important. Also I have discovered that variations in the distance between the discharging tip of the nozzle and the points of impact of the jet with the bark have a direct bearing on the efficiency of the debarking jet and that; in general, the effectiveness of the jet in breaking up and removis increased. Consequently in designing a hydraulic log-barking machine in which the nozzle will automatically adjust itself for logs of various sizes and shapes, a chief difliculty which I encountered was the charging tip of the nozzle always sufficiently close to the log surface and at the same time keeping the jet directed in the proper manner. In solving this problem with my invention the reverse curve at the free end of the nozzle and the location of the fixed pivotal point of the nozzle with respect to the log'axis, as provided in my construction, are essential features. It will be apparent from Fig. 3 that the pivotal point of the nozzle is at a fixed distance from the axis of the log and that the pivotal point and the discharging tip of the nozzle are located in adjacent log quadrants and will never be in the same quadrant. By having the pivotal point of the nozzle suflicient distance from the log axis (thus sulficient distance above and to the right of the axis as viewed in Fig. 3) this feature of havin the nozzle tip and the pivotal point of the nozzle in different quadrants is maintained for both large and small logs as evident from Fig. 3. Due to the fact that the free end of the nozzle, during the debarking operation, is supported on the shoe which in turn ride on the surface of the log, and due to the fact that the location of the nozzle tip is fixed with respect to the shoe, the distance of the nozzle tip from the surface of the log, and thus the distance from nozzle tip to point of impact of the jet with the log, will vary very slightly, if at all, with difierent sizes of logs.

This important feature of my invention i illustrated diagrammatically in Fig. 7 in which d indicates the pivotal point of the nozzle, a is the ing the bark decreases rapidly as this distance the logs c, e and 3 axis of the, log in each case, 0, e, and f indicate logs of different diameters, and b' b and b represent corresponding positions of the nozzle tip. The distances of the nozzles b3, b andb from I f respectively will be found to be approximately the same.

In a log clebarking machine embodying this invention, which is at present in actual operation, the distance from nozzle tip to point of jet impact measures approximately 6 inches where the diameter of the log is 54 inches; 6% inches where the diameterof the log is 36 inches; 6% inches where the diameter of the log is 24 inches; and 6% inches where the diameter of the log is 12' inches; thus bearing out this feature of'my invention. In the machine referred to in the previous sentence thesize of the jet as discharged from the nozzle tip is approximately 4% inches by M; inch, the nozzle discharges at the rate of about ten barrels per minute and the speed of the jet as it leaves the nozzle tip is about 275 feet per second. I mention these figures merely by way of illustration, inasmuch as the machine to which I refer and which is in use has been found highly efiicient particularly for hemlock logs of the ordinary range of sizes.

By experiment I found that most efficient debarklng is obtained when the Jet strikes the surface of the log at such an angle that the center line of the jet would, if the log were cut transversely at that point, constitute a chord on the circular cut surface, cutting oil a small segment inside the inner bark line, such as indicated by the broken line :i in Fig; 7. Since the pivotal point d of the nozzle and the axis a of the log are relatively fixed, and since the discharging tip of,

the nozzle is always a constant radial distance from the pivotal point d, the center line of the problem of keeping the dis- Jet, when the nozzle is used for debarking logs of different sizes would tend to be tangent to some imaginary circle of which d is the center, such as the circle indicated by the arc k in Fig. 7, the radius of the circle is, depending upon the curvature given the nozzle. With the arrangement of the nozzle and location of the pivotal point d as indicated in Fig. '7 it will be found that the angle at which the jet strikes the surface of the log (thus the angle a: formed by the intersection of the chord a and a tangent 1/ at the point of impact), will be substantially thesame regardless of the sizes of logs used.

Since the nozzle-supporting carriage, in the preferred form in which I carry out my invention, is located above the log, I have found it more satisfactory to use an for supplying the water to the nozzle instead'of the usual flexible hose.

tion by the air cylinder and associated means on the carriage. After the log has been placed in position in the machine and is being rotated and the carriage is atthe rear end of the log, the

nozzle is lowered until the nozzle shoe rests on articulated pipe connection Referring to Figs. 1, 2 and 3, the pipe 44, connected toasuitable source operation, as already indicated, is a relatively'simple matter. Preparatory to the debarking, the nozzle is supported in raised posifrom the nozzle will strike always be in T 1 ncmle is located I the nozzle are required. All that is necessary for the operator to do is to watch to see if the log is being rotated at the proper speed so that all the bark is being removed by the jet but none of the wood under the'bark, and to increase or decrease the speed of rotation as required if this is not the case. When the debarking is completed and the carriage has reached the forward limit of its travel the nozzle is raised and the carriage is returned swiftly to the rear of the machine while the log is being removed and a new log set in its The entire debarking operation is thus controlled merely by controlling the speed at which the log is rotated in the machine. Since the jet the bark at the predetermined desired distance from the discharging tip of the nozzle, and since the jet will also strike the bark at the predetermined desired angle at all times, the most efficient use of the debarking jet is assured and is obtained without any adjustment of the nozzle regardless of the size of the log or of any variations in the size and shape of the log. Thus practically no skill is required on the part of the operator when debarking with this machine.

Since the carriage travels only once from the rear end of the log to the forward end of the log during the entire debarking operation, all waste of time in having and forth during the debarking is avoided. This is an advantage over certain other types of hydraulic debarking machines in which the nozzle carriage is obliged to move back and forth in- {rumerable times in the debarking of a single A further important advantage of my machine is the fact that the debarking operation can be carried out just as efllciently with crooked logs as with straight ones, and in this respect my machine is believed to be much superior to other hydraulic debarking machines which are limited more or less to use with straight and regularlyformed logs. The debarking of crooked and irregular logs heretoiore has constituted somewhat of a problem.

Fig. 8 illustrates diagrammatically a crooked log m assumed to be in the machine described. As the log mis rotated and the carriage in the machine moves the nozzle from left to right (as viewed in Fig. 8), the nozzle b will occupy the successive relative positions indicated by b with each complete rotation of the log. Since the nozzle shoe rests on the log at'all times the noz-' zle, with each successive rotation of the log, will the same relative position with respect to that portion of the log surface which is being debarked,and same spiral path 9 as log.

Many modifications could be made. in the machine which I have illustrated and described without departing from the principle of my invention. I believe it is essential, however, to accomplish fully the objects of my inventio in the case of a straight zle in which the pivotalpoint is located on one side of the log while the discharging tip of the at the othersideoi the lo and also to term the nozzle with a curve adiathe carriage moved back cent the tip in order to have. the dcbarking jet directed against the log at a fairly constant angle of impingement.

I claim:

,1. In a log-barking machine of the character described, including means for supporting the log for rotation and a carriage movable in a plane ,machine for the purposes described, including point, the location parallel to the rotational axis of the log, a debarking nozzle, said nozzle pivotally mounted on said carriage so as to swing in a plane perpendicular to the rotational axis of the log, a reverse curve in said nozzle between the discharging tip of said nozzle and said pivotal point, the location of said pivotal point and the distance or the discharging nozzle tip from said pivotal point adapted to cause said tip and said always to be on opposite sides of a log in the described.

2. In a log-barking machine of the character means for supporting the log for rotation, a carriage. movable longitudinally of the log and parallel to the rotational axis of the log, a debarking nozzle, said nozzle pivotally mounted on said carriage so as to swing in a plane perpendicular to the rotational axis of the log, said carriage and-nozzle so arranged that the pivotal point of said nozzle will be a fixed distance from the rotational axis of the log at all times, a reverse curve in said nozzle between the discharging tip of said nozzle and said pivotal of said p ivotal point and the distance of the discharging nozzle tip from said pivotal point adapted'to cause said tip and said pivotal point always to be on opposite sides of the debarking follows the in order 70. to employ a pivotally-mounted debarking noz-- l. a log in the machine, a shoe-connected to said nozzle, said shoe adapted to rest against the surface of the log during the debarking and to keep the nozzle tip spaced a predetermined substantially fixed distance from the log surface, said reverse curve in said nozzle so arranged as to cause the jet from said nozzle to bedischarged in a general direction towards said pivotal point, whereby the jet from said nozzle tip will strike the log surface at a substantially constant and predetermined angle when the nozzle is in debarking position regardless of the size of the log.

3. In a log-barking machine of the character described, including means ior supporting the log for rotation and a carriage movable longitudinally of the log, a debarking nozzle, said nozzle pivotall mounted on said carriage so as to swing in a plane perpendicular to the rotational axis of the log, a reverse curve in said nozzle between the discharging tip of said nozzle and said pivotal point, the location of said pivotal point and the distance of the discharging nozzle tip from said pivotal point, adapted to cause said tip and said pivotal point always to be on opposite sides of a log in the machine for the purposes described, a shoe mounted on said nozzle, said shoe adapted to ride on the surface of the log during the debarking and to keep the nozzle tip spaced a predetermined substantially fixed distance from the means operated by fluid pressure, mounted on said carriage and connected with said nozzle, for holding said nozzle and shoe in debarking position and for lifting said nozzle and shoe out or debarking position.

4. The combination described in claim 3 with said shoe having side walls and a top portion adapted to act also as a shield in confining and directing the course of bark fragments produced by the nozzle iet.-

5.1m a log-barking machine or the character pivotal point described, includingmeans for supporting the log for rotation, a carriage movable longitudinally of the log and parallel to the rotational axis of; the log, a debarking nozzle, said nozzle pivotally mounted on said carriage so as to swing in a plane perpendicular to the rotational axis of the log, said carriage and nozzle so arranged that the pivotal point of said nozzle will be a on said nozzle, said shoe adapted to ride on the surface of the log during the debarking and to keep the nozzle tip spaced a predetermined substantially fixed distancevfrom the log surface, said reverse curve in said nozzle so arranged as to cause the jet from said nozzle to be discharged in a general direction towards said pivotal point, -whereby the jet from said nozzle tip will strike the log surface at asubstantiall constant and predetermined angle'when the nozzle is in debarking position regardless of the size of the log, means supported on said carriage and connected with said nozzle and adapted to aid in automatically holding said nozzle and shoe in debarking position regardless of irregularities in the log surface, a supply pipe on said carriage connected to said nozzle, and means including articulated pipe sections on said machine for connecting said supply pipe with a source of water under pressure.

6. In a log-barking machine of the character described, including means for supporting the log for rotation, means for rotating the log, a

carriage movable longitudinally of the log and parallel to the rotational axis of the log, a debarking nozzle, said nozzle pivotally mounted on said carriage so as to swing in a plane perpendicular to the rotational axis of the log, a, reverse curve in said nozzle between the discharging tip of said nozzle and said pivotal point, the locacarriage will move at a predetermined speed ratio with respect to the rotation of. the log,

whereby a change in speed of rotation will automatically cause corresponding change in the speed of travel of said carriage and nozzle and whereby the speed at which the debarking is done can be controlled merely by adjusting the speed of rotation of the log.

7. Thecombination described in claim 6 with said shoe having side walls and a top portion adapted to act also as a shield in confining and directing the course of bark fragments produced by the nozzle jet, and means supported on said carriage and connected with said nozzle and adapted to aid in automatically holding said nozzle and shoe in debarking position regardless of irregularities in the log surface.

ihIn a log-barking machine of the character described, including means for supporting the log for rotation, a carriage movable longitudinally'of the log, a debarking nozzle pivotally mounted on said carriage for movement in a plane substantiall perpendicular to the plane of travel of said carriage, a discharging tip at the free end of said nozzle, a shoe connected-with said nozzle, said shoe adapted to ride on-the surface of the log and thereby to hold the tip of said nozzle a desired distance from the log surface at all times,

discharging tip being such that they will be located at opposite sides of the log for the-purposes described.

tion of said pivotal point and the distance of log during the debarking and to keep the nozzle.

tip spaced a predetermined substantially fixed distance from the log surface, means for moving said carriage, said carriage moving means con-' nected with said log rotating means so that said 9. In a hydraulic log-barking machine of the character described, means for supporting the log for rotation, means for rotating the log, a carriage movable longitudinally of the log, means for moving said carriage, a nozzle assembly pivotally supported on said carriage for movement in a plane substantially perpendicular to the line 7 ing a discharging tip, and a curve adjacent the located in adjacent log quadrants whereby said nozzle assembly will automatically accommodate itself to variations in the diameter of the log and to logs of various diameters.

' HARRY E. BUKOWSKY. 

